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At least 343 records · Page 19

12-gene prognostic signature for breast cancer survival

A biomarker panel of 12 genes based on expression levels. Methods for calculating prognostic scores and patient ranking based on their score and divided into two equal sized cohorts. Kaplan-Meier analysis and a log-rank test were used to determine differences in survival.

Snijders, Antoine M.↗

IMPROVED Co i log(gf) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

New emission branching fraction measurements for 898 lines of the first spectrum of cobalt (Co i) are determined from hollow cathode lamp spectra recorded with the National Solar Observatory 1 m Fourier transform spectrometer on Kitt Peak, AZ and a high-resolution echelle spectrometer. Published radiative lifetimes from laser induced fluorescence measurements are combined with the branching fractions to determine accurate absolute atomic transition probabilities for the 898 lines. Hyperfine structure (hfs) constants for levels of neutral Co in the literature are surveyed and selected values are used to generate complete hfs component patterns for 195 transitions of Co i. These new laboratory data are applied to determine the Co abundance in the Sun and metal-poor star HD 84937, yielding log ϵ(Co) = 4.955 ± 0.007 (σ = 0.059) based on 82 Co i lines and log ϵ(Co) = 2.785 ± 0.008 (σ = 0.065) based on 66 Co i lines, respectively. A Saha or ionization balance test on the photosphere of HD 84937 is performed using 16 UV lines of Co ii, and good agreement is found with the Co i result in this metal-poor ([Fe i/H] = −2.32, [Fe ii/H] = −2.32) dwarf star. The resulting value of [Co/Fe] = +0.14 supports a rise of Co/Fe at low metallicity that has been suggested in other studies.

79 ASTRONOMY AND ASTROPHYSICS↗

Chemoembolization Decreases Drop-Off Risk of Hepatocellular Carcinoma Patients on the Liver Transplant List

Introduction: The drop-off risk for patients awaiting liver transplantation for hepatocellular carcinoma (HCC) is 22%. Transplant liver availability is expected to worsen, resulting in longer waiting times and increased drop-off rates. Our aim was to determine whether chemoembolization can decrease this risk. Patients and Methods: Eighty-seven consecutive HCC patients listed for liver transplant (Milan criteria) underwent statistical comparability adjustments using the propensity score (Wilcoxon, Fisher's, and chi-square tests). Forty-three nonchemoembolization patients and 22 chemoembolization patients were comparable for Child-Pugh and Model for End-Stage Liver Disease scores, tumor size and number, alpha fetoprotein (AFP) levels, and cause of cirrhosis. We calculated the risk of dropping off the transplant list by assigning a transplant time to those who dropped off (equal probability with patients who were on the list longer than the patient in question). The significance level was obtained by calculating the simulation distribution of the difference compared with the permutations of chemoembolization versus nonchemoembolization assignment of the patients. Kaplan-Meier estimators (log-rank test) were used to determine survival rates. Results: Median follow-up was 187 {+-} 110 weeks (range 38 to 435, date of diagnosis). The chemoembolization group had an 80% drop-off risk decrease (15% nonchemoembolization versus 3% chemoembolization, p = 0.04). Although survival was better for the chemoembolization group, it did not reach statistical significance. Two-year survival for the nonchemoembolization and chemoembolization group was 57.3% {+-} 7.1% and 76.0% {+-} 7.9%, respectively (p = 0.078). Conclusions: Chemoembolization appears to result in a significant decrease in the risk of dropping off liver transplant list for patients with HCC and results in a tendency toward longer survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Reactive transport in the complex heterogeneous alluvial aquifer of Fortymile Wash, Nevada

Yucca Mountain, Nevada, had been extensively investigated as a potential deep geologic repository for storing high-level nuclear wastes. Previous field investigations of stratified alluvial aquifer downstream of the site revealed that there is a hierarchy of sedimentary facies types. There is a corresponding log conductivity and reactive surface area subpopulations within each facies at each scale of sedimentary architecture. Here in this paper, we use a Lagrangian-based transport model in order to analyze radionuclide dispersion in the saturated alluvium of Fortymile Wash, Nevada. First, we validate the Lagrangian model using high-resolution flow and reactive transport simulations. Then, we used the validated model to investigate how each scale of sedimentary architecture may affect long-term radionuclide transport at Yucca Mountain. Results show that the reactive solute dispersion developed by the Lagrangian model matches the ensemble average of numerical simulations well. The link between the alluvium spatial variability and reactive solute dispersion at different spatiotemporal scales is demonstrated using the Lagrangian model. Finally, the longitudinal dispersivity of the reactive plume can be on the order of hundreds to thousands of meters, and it may not reach its asymptotic value even after 10,000 years of travel time and 2–3 km of travel distance.

54 ENVIRONMENTAL SCIENCES↗

Timing of Salvage Hormonal Therapy in Prostate Cancer Patients With Unfavorable Prognosis Treated With Radiotherapy: A Secondary Analysis of Radiation Therapy Oncology Group 85-31

Purpose: Radiation Therapy Oncology Group 85-31 was a randomized trial comparing radiotherapy (RT) alone vs. RT plus adjuvant androgen suppression for life in unfavorable-prognosis carcinoma of the prostate. We examined the impact of early initiation of salvage hormonal therapy (HT) in relapsing patients randomized to RT alone arm. Methods and Materials: Patients were divided into two groups: early salvage HT and late salvage HT. The early salvage group was defined as receiving HT with a prostate-specific antigen (PSA) level of less than 10 ng/mL, and the late salvage HT group had a PSA level of 10 ng/mL or greater. The outcomes were overall survival (OS), cause-specific mortality (CSM), and local failure (LF). The Kaplan-Meier estimation and log-rank test were used for OS, and the cumulative incidence estimation and Gray's test were used for CSM and LF. Proportional hazards regression models were used to compare the outcomes adjusted for other covariates. Results: The median follow-up times of surviving patients in the early and late salvage HT groups were about 11 and 13 years, respectively. The late salvage HT group had significantly more post-prostatectomy patients and patients with high Gleason scores. After adjustment for all covariates, OS was significantly longer in the early salvage HT group (hazard ratio, 1.5; p = 0.01). However, there were no statistically significant differences in LF or CSM between the groups. Conclusions: The early introduction of salvage HT resulted in improved OS but not improved CSM and LF. A randomized trial to define the optimal salvage hormonal timing is warranted in this group of patients with PSA recurrence after RT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Turbulence Structures in the Very Stable Boundary Layer Under the Influence of Wind Profile Distortion

Abstract In very stable boundary layers (VSBL), a “cocktail” of submeso motions routinely result in elevated mean wind speed maxima above the ground, acting as a new source of turbulence generation. This new source of turbulent kinetic energy enhances turbulent mixing and causes mean wind profile distortion (WPD). As a results, this transient distortion in the wind profile adjusts the classical log‐law. Addressing how WPD‐induced turbulence regulates flow structures, turbulent fluxes, and transitions in stability regimes across layers remains a challenge. Eddy covariance data measured at four levels on a 62‐m tower are employed to address these questions. It is shown that the WPD initiates large turbulent eddies that penetrate downward, leading to enhanced vertical mixing and comparable turbulent transport efficiencies across layers. As a consequence, turbulence intensity and fluxes are increased. As the WPD is intensified, turbulent fluxes and turbulent flux transport caused by large eddies are also enhanced, leading to a transition from very stable to weakly stable regimes. Due to the influence of WPD‐induced large eddies, the large‐eddy turbulent Prandtl number does not deviate appreciably from unity and the partitioning between turbulent kinetic and potential energies is linearly related to the gradient Richardson number.

Meteorology & Atmospheric Sciences↗

Reconstruction of the primordial power spectrum from CMB data

Measuring the deviation from scale invariance of the primordial power spectrum is a critical test of inflation. In this paper we reconstruct the shape of the primordial power spectrum of curvature perturbations from the cosmic microwave background data, including the 7-year Wilkinson Microwave Anisotropy Probe data and the Atacama Cosmology Telescope 148 GHz data, by using a binning method of a cubic spline interpolation in log-log space. We find that the power-law spectrum is preferred by the data and that the Harrison-Zel'dovich spectrum is disfavored at 95% confidence level. These conclusions hold with and without allowing for tensor modes, however the simpler model without tensors is preferred by the data. We do not find evidence for a feature in the primordial power spectrum — in full agreement with generic predictions from cosmological inflation.

79 ASTRONOMY AND ASTROPHYSICS↗

2002 St. Louis Region Travel Survey

The 2002 St. Louis Household Travel Survey entailed the collection of weekday travel behavior characteristics of households residing in each of the eight counties that comprise the St. Louis region. In addition to collecting basic demographic and socioeconomic information about each household and its members, the survey documented specific characteristics of activities and trips, including the number and purpose of trips, trip duration, time of day, mode of transportation, and specifics of school- and work-related travel. The survey instruments contained three components: 1) the recruitment questionnaire, 2) the travel log, and 3) the retrieval questionnaire. In total, 7,046 households were recruited to participate in the study via telephone interview. Of these, 5,094 completed travel logs during a specific 24-hour period, and the information was retrieved from all household members, regardless of age. Demographic information for this study includes age, gender, education level, employment status, and household income.

1Hz data↗

ML-Based Rock Properties and Seismic Volume Enhancement

This project aims to improve field-scale Carbon Capture and Storage (CCS) assessments by enhancing petrophysical and geophysical log predictions through machine learning and neural networks. In our work during EY23, we applied Conditional Variational Autoencoders (CVAEs) to predict compressional velocity (Vp) and assess CO2 saturation levels in geological formations at the Illinois Basin Decatur Project (IBDP). In another task, we improved full-waveform inversion (FWI) methods with machine-learning approaches using lithological constraints. Full-waveform inversion (FWI) of seismic data estimates the elastic properties of subsurface rocks with high spatial resolution.

Nathanail, Athanasios↗

Amplicon Sequencing Reveals Microbiological Signatures in Spent Nuclear Fuel Storage Basins

Water quality is an important determinant for the structural integrity of alloy cladded fuels and assemblies during long-term wet storage. Detailed characterization of a water filled storage basin for spent nuclear reactor fuel was performed following the formation and proliferation of an amorphous white flocculent. White precipitant was sampled throughout the storage basin for chemical and spectroscopic characterization, and eDNA was extracted for pyrosequencing of bacterial rRNA gene diversity. Accordingly, spectroscopic analyses indicated the precipitant to be primarily amorphous to crystalline aluminum (oxy) hydroxides with minor associated elemental components including Fe, Si, Ti, and U. High levels of dissolved carbon were co-localized with the precipitant relative to bulk water. Bacterial densities were highly variable between sampling locations and with depth; cell numbers (log scale) ranged from 5.6 to 4.89 cells / mL. Bacterial diversity that was physically associated with the aluminum (oxy) hydroxide complexes exceeded an estimated 4,000 OTUs / amplicon library (3% cutoff) and the greatest percent majority of sequences were aligned to the families Burkholderiales (23%), Nitrospiraceae (23%), Hyphomicrobiaceae (17%), and Comamonadaceae (6%). We surmise that episodic changes in the physical and chemical properties of the basin contribute to the polymerization of aluminum (oxy) hydroxides, which in turn can chemisorb nutrients, carbon ligands and bacterial cells from the surrounding bulk aqueous phase. As such, these precipitants should establish favorable microhabitats for bacterial colonization and growth. Comparative analyses of 16S rRNA gene amplicon libraries across diverse environmental landscapes were performed and microbiological signatures unique to the spent nuclear fuel storage basin environment were revealed. These insights could spur the development of tractable bioindicators that are specific of and diagnostic for water quality at discrete locations and finer scales of resolution, marking an important contribution for improved water quality and management of spent nuclear fuel storage facilities.

aluminum↗

Metals exposure and risk of small-for-gestational age birth in a Canadian birth cohort: The MIREC study

Background: Lead, mercury, cadmium and arsenic are some of the most common toxic metals to which Canadians are exposed. The effect of exposure to current low levels of toxic metals on fetal growth restriction is unknown. Objective: The aim of this study was to examine relationships between exposure to lead, mercury, cadmium and arsenic during pregnancy, and risk of small for gestational age (SGA) birth. Methods: Lead, mercury, cadmium and arsenic levels were measured in blood samples from the first and third trimesters in 1835 pregnant women from across Canada. Arsenic species in first trimester urine were also assessed. Relative risks and 95% confidence intervals were estimated using log binomial multivariate regression. Important covariates including maternal age, parity, pre-pregnancy BMI, and smoking, were considered in the analysis. An exploratory analysis was performed to examine potential effect modification of these relationships by single nucleotide polymorphisms (SNPs) in GSTP1 and GSTO1 genes. Results: No association was found between blood lead, cadmium or arsenic and risk for SGA. We observed an increased risk for SGA for the highest compared to the lowest tertile of exposure for mercury (>1.6 µg/L, RR=1.56.; 95% CI=1.04–2.58) and arsenobetaine (>2.25 µg/L, RR=1.65; 95% CI=1.10–2.47) after adjustment for the effects of parity and smoking. A statistically significant interaction was observed in the relationship between dimethylarsinic acid (DMA) levels in urinary arsenic and SGA between strata of GSTO1 A104A (p for interaction=0.02). A marginally significant interaction was observed in the relationship between blood lead and SGA between strata of GSTP1 A114V (p for interaction=0.06). Conclusions: These results suggest a small increase in risk for SGA in infants born to women exposed to mercury and arsenic. Given the conflicting evidence in the literature this warrants further investigation in other pregnant populations. - Highlights: • Metals measured in blood or urine of pregnant women. • No association between blood lead, cadmium or arsenic and SGA. • Small increased risk for highest tertile of blood mercury. • Small increased risk for highest tertile of urinary arsenobetaine. • Further research needed to confirm observed associations.

54 ENVIRONMENTAL SCIENCES↗

Innovative Data Management System in Support of Remedial Actions for Legacy Radioactive Contamination - 17280

The Port Hope Area Initiative (PHAI) is a project mandated and funded by the Government of Canada to remove contamination from properties with legacy low-level radioactive waste (LLRW) contamination arising from a crown-owned radium and, later, uranium refinery in the Town of Port Hope, Ontario. From 1976 to 1981, a community clean-up project was undertaken, with the specific purpose to decrease the level of historic LLRW contamination within Port Hope. Since then, residual LLRW has been managed by the Low Level Radioactive Waste Management Office (LLRWMO) (and its predecessors). The PHAI and the Port Hope Project (PHP) were initiated in 2001 with a formal agreement between affected municipalities and the federal government to develop a safe, long-term management solution for the historic LLRW remaining within Port Hope. An important activity of the PHP is the survey of about 4,800 'small scale sites' (SSS) throughout the community to confirm the presence or absence of LLRW. This involves surveys of properties based on the measurement of exterior gamma, contaminated objects and surfaces, soil concentrations and indoor radon and classification to Port Hope project specific criteria. A very large amount of information is involved in the project including; scheduling individual field visits to the properties, capture of field data and comments, laboratory sample tracking, QA/QC, report generation and internal and client project reporting at regular schedules. Field data collection of exterior gamma radiation surveys includes direct (real time) and interactive loading of data into the Information Management (IM) system to support initial QA/QC and reporting back to the field on radiation levels. Screening soil measurements including X-ray fluorescence (XRF) and gamma radiation are collected from all 20 cm increments in each borehole in addition to down-hole gamma radiation measurements and logging of soil characteristics which are used in documentation and interpretation of the property condition. The IM system outlined in this paper was developed to respond to the requirements for radiological surveys in Port Hope. The IM system continues to evolve as a part of continuing review and improvement. The IM system incorporates Web-enabled field tools and cloud hosted data and applications, provides increased field efficiency, timeliness in reporting, real time QA/QC analysis, and consistency in tracking project advances and changes made to the data for decision-making and reporting on an ongoing basis. Examples of specific applications are provided. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Microtron Data Log

The Microtron at Los Alamos National Laboratory (LANL) is a versatile electron accelerator originally designed for medical therapy. Since 2001, it has been used for non-destructive radiographic imaging and research and development applications. Operating at four different energy levels—6, 10, 15, and 20 MeV—the Microtron produces dose rates of approximately 780, 1800, 2700, and 2800 R/min at a distance of one meter from the source, respectively. This high-energy X-ray source enables detailed internal examination of dense and thick objects without causing damage, making it invaluable for various scientific and industrial applications. For instance, LANL’s Microtron has been utilized to study the performance of large-panel cerium-doped lutetium yttrium silicon oxide (LYSO) scintillators, which are essential components in advanced imaging systems.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DEDUPKV: A Space-Efficient and High-Performance Key-Value Store via Fine-Grained Deduplication

Log-Structured Merge Tree (LSM-tree) based key-value stores excel in write-intensive environments but suffer from data duplication, consuming up to 49% of storage space in LSM-tree-based key-value store deployments. Traditional solutions like compression and coarse-grained file system-level deduplication introduce overhead or have limited effectiveness. In this study, we propose DedupKV, a fine-grained deduplication framework tailored for LSM-tree, maximizing data reduction efficiency while minimizing write stalls and read overheads. DedupKV features three key innovations: (1) FLUSH-integrated inline deduplication, which removes duplicates during memory-to-storage writes; (2) WAL file-based offline deduplication, repurposing write-ahead logs to avoid double writes; and (3) elastic execution, dynamically balancing inline and offline deduplication based on memory pressure and workload intensity. Additionally, dynamic granularity management reduces deduplication metadata overhead. We implemented these four ideas in RocksDB for the first time and conducted experiments in a Linux environment. Our evaluation shows that WAL file-based offline deduplication and DedupKV outperform BlobDB by 33% and 23%, respectively, in write-heavy workloads, while reducing write amplification by 1.2 ×, 2 ×, and 1.6 × for real KV datasets.

Jamil, Safdar [Sogang University]↗

Direct Laser Writing of Low-Density Interdigitated Foams for Plasma Drive Shaping [Direct Laser Writing of Low Density Nanostitched Foams for Plasma Drive Shaping]

Monolithic porous bulk materials have many promising applications ranging from energy storage and catalysis to high energy density physics. High resolution additive manufacturing techniques, such as direct laser writing via two photon polymerization (DLW-TPP), now enable the fabrication of highly porous microlattices with deterministic morphology control. In this work, DLW-TPP is used to print millimeter-sized foam reservoirs (down to 0.06 g cm –3 ) with tailored density-gradient profiles, where density is varied by over an order of magnitude (for instance from 0.6 to 0.06 g cm –3 ) along a length of <100 µm. Taking full advantage of this technology, however, is a multiscale materials design problem that requires detailed understanding of how the different length scales, from the molecular level to the macroscopic dimensions, affect each other. The design of these 3D-printed foams is based on the brickwork arrangement of 100 × 100 × 16 µm 3 log-pile blocks constructed from sub-micrometer scale features. A block-to-block interdigitated stitching strategy is introduced for obtaining high density uniformity at all length scales. Lastly, these materials are used to shape plasma-piston drives during ramp-compression of targets under high energy density conditions created at the OMEGA Laser Facility.

36 MATERIALS SCIENCE↗

PyDSS

PyDSS is a high level python interface for OpenDSS and provides the following functionalities 1] Object oriented programming 2] Dynamic visualization 3] Custom controls 4] Simulation parallelization 5] Exporting results 6] Improved Error logging 7] Communication interface

Latif, Aadil↗

PyDSS

PyDSS is a high level Python interface for OpenDSS and provides the following functionalities: 1] Object oriented programming, 2] Dynamic visualization, 3] Custom controls, 4] Simulation parallelization, 5] Exporting results, 6] Improved error logging, and 7] Communication interface. Documentation on installation, setup and examples can be found here https://nrel.github.io/PyDSS/index.html

Latif, Aadil↗

The Extended IRTF Spectral Library: Expanded Coverage in Metallicity, Temperature, and Surface Gravity

We present a 0.7–2.5 μm spectral library of 284 stars observed with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Maunakea, Hawaii. This library extends the metallicity range of the IRTF Cool Star library beyond solar metallicity to −1.7 < [Fe/H] < 0.6. All of the observed stars are also in the MILES optical stellar library, providing continuous spectral coverage for each star from 0.35 to 2.5 μm. The spectra are absolute flux calibrated using Two Micron All Sky Survey photometry, and the continuum shape of the spectra is preserved during the data reduction process. Synthesized JHK {sub S} colors agree with observed colors at the 1%–2% level, on average. We also present a spectral interpolator that uses the library to create a data-driven model of spectra as a function of T{sub eff}, log g, and [Fe/H]. We use the library and interpolator to compare empirical trends with theoretical predictions of spectral feature behavior as a function of stellar parameters. These comparisons extend to the previously difficult to access low-metallicity and cool dwarf regimes, as well as the previously poorly sampled super-solar metallicity regime. The library and interpolator are publicly available.

79 ASTRONOMY AND ASTROPHYSICS↗